Maus Gerrit W, Whitney David
Division of Psychology, School of Humanities and Social Sciences, Nanyang Technological University, Singapore.
Department of Psychology, University of California, Berkeley, California, United states of America.
PLoS One. 2016 Apr 21;11(4):e0153896. doi: 10.1371/journal.pone.0153896. eCollection 2016.
We usually do not notice the blind spot, a receptor-free region on the retina. Stimuli extending through the blind spot appear filled in. However, if an object does not reach through but ends in the blind spot, it is perceived as "cut off" at the boundary. Here we show that even when there is no corresponding stimulation at opposing edges of the blind spot, well known motion-induced position shifts also extend into the blind spot and elicit a dynamic filling-in process that allows spatial structure to be extrapolated into the blind spot. We presented observers with sinusoidal gratings that drifted into or out of the blind spot, or flickered in counterphase. Gratings moving into the blind spot were perceived to be longer than those moving out of the blind spot or flickering, revealing motion-dependent filling-in. Further, observers could perceive more of a grating's spatial structure inside the blind spot than would be predicted from simple filling-in of luminance information from the blind spot edge. This is evidence for a dynamic filling-in process that uses spatiotemporal information from the motion system to extrapolate visual percepts into the scotoma of the blind spot. Our findings also provide further support for the notion that an explicit spatial shift of topographic representations contributes to motion-induced position illusions.
我们通常不会注意到盲点，即视网膜上无感受器的区域。延伸穿过盲点的刺激似乎是完整的。然而，如果一个物体没有穿过盲点而是在盲点处终止，它在边界处会被视为“截断”。在这里，我们表明，即使在盲点相对边缘没有相应刺激时，众所周知的运动诱导位置偏移也会延伸到盲点，并引发一个动态填充过程，该过程允许将空间结构外推到盲点中。我们向观察者展示了向盲点内或盲点外漂移或反相闪烁的正弦光栅。移入盲点的光栅被感知为比移出盲点或闪烁的光栅更长，这揭示了与运动相关的填充。此外，观察者在盲点内能够感知到的光栅空间结构比根据从盲点边缘简单填充亮度信息所预测的要多。这证明了一个动态填充过程，该过程利用来自运动系统的时空信息将视觉感知外推到盲点的暗点中。我们的发现还进一步支持了这样一种观点，即地形表征的明确空间偏移导致了运动诱导的位置错觉。
